Process for the manufacture of derivatives of vat dyestuffs



June 16, 1 1- H. A. E. DRESCHER ET AL 1,810,758

PROCESS FOR THE MANUFACTURE OF DERIVATIVES 0F VAT DYESTUFFS Filed March3, 1927 I NH NH OCH NaO.SO .O g-

N so so (P 9) adapted to Patented June 16, 1931 UNITED STATES PATENTOFFICE HUGH ALBERT EDWARD DBESCHER, JOHN EDMUND GUY HARRIS, 3mm WY'LAM,,AND JOHN THOMAS, OF GBANGEMOUTH, SCOTLAND, ASSIGNOBS TO SCOTTISH DYES,

DIMITED, OI GRANGEMOUTH, SCOTLAND PROCESS FOR THE MANUFACTURE OFDERIVATIVES 01' VAT DYESTUFFS Application filed March 3, 1927, SerialNo. 172,550, and in Great Britain Iamh 15, 1926.

This invention relates to the manufacture and use of d estufl'derivatives prepared from vat dyestufl s In British specification No.247,787, filed August 11th, 1924, there isdescribed the preparation ofderivatives of vat dyestufi's by interaction of the vat dyestufi's witha meta and chloro-sulphonic acid or the like in the presence of atertiary amine and analogous matters.

The object of the present invention is to provide improved or furthermethods for preparing derivatives of vat dyestufi's, wh ch derivativespossess the roperty of belng capable of employment or dyeing without theusual vat process.

The invention consists in a process for the manufacture of derivativesof vat dyestuffs comprising the reaction between a quaternary ammoniumhalide which may be obtained by reaction between a tertiary organic baseand an alkyl halide, in tertiary organic basic susnsion with a metal, avat dyestufi and a product obtained bythe interaction of a tertiaryorganic base with a reagent adapted to yield the sulphuric anhydridecompound of the tertiary base for example an alkyl chlor sulphonate,sulphuric acid mono-chloride (chlor-sulphonic acid) oleum, or sulphurtrioxide.

The invention also consists in a process for the manufacture ofderivatives of vat dyestufis according to which a quaternar ammoniumhalide which may be obtained y reaction between a tertiary organic baseand an alkyl halide is caused to react in tertiary organic basicsuspension with a metal and the resulting mixture to react with a vatdyestufi', the product then being subjected to the reaction ofa compoundof a tertiary organic base formed by the addition of a reagent 'eld thesulphuric anhydride compound 0' the tertiary base for exam le an alkylchlor sulphonate, sulphuric acldmono chloride (chlor sulphonic acid)oleum, or sulphur trioxide to pyridine or other tertiary organic base.

The invention also consists in methods for preparing vat dyestuffsderivatives substantially as herein described. I

tion of the products of the processes indicated above to dyeing andrinting.

The invention inc udes vat dyestuii derivatives which can be prepared bythe processes described or by their obvious chemical equivalents.

The invention also consists in dyed and printed products which can beprepared by processes substantially as herein described or by theirobvious chemical equivalents.

Referring to the accompanying diagrammatic drawings, which give probableconstitutlonal formulae of the bodies to which they refer, but do nottake into account water of crystallization, associated with thecompound, which may vary according to the methods used duringcrystallization and dry- E'wwmple 1 This is an example illustrating theemployment of indigo, methyl pyridinium iodide, zinc and pyridinefollowed by treatment with the 'product' of pyridine and methylchlor-sulphonate.

5 parts of methyl pyridinium iodide (prepared for example by adding.3.25 parts of methyl iodide to 1.8 parts of pyridine) aresuspended inpyridine in a vessel and with good stirring 1.5 parts of finely dividedzinc are added. To this mixture there-are then added 1.5 parts of dryindigo and the mixture efliciently stirred.

Enough pyridine is employed to give a no thick but workable paste, thepyridine thus employed being in excess of the theoretical quantityrequired.

To the suspension there are added 4.8 parts of the additive compoundformed by the addition of pyridine to methyl chlor-sulphonnatc. Thecontents are Well stirred and heated to 30 to 40 C. for a short time.The melt is then worked up in the usual way. For example, it.can be madealkaline with soda ash solution and excess of p ridine distilled ofl insteam. The residue in t is still is then extracted with boiling waterand the filtrate concen trated and cooled.

The product can be employed for dyeing and printing; for examplefabrics, for instance, can be padded in the water solution of theproduct and the dye formed on the fibre by the addition of an acidoxidizing agent.

In connection with this process the following gives our present view ofthe reaction in the case of indigo:

The zinc reacts with the methyl pyridinium iodide. On addition of theindigo a reaction takes place and the melt becomes red due apparentl tothe formation of a red compound of the estuff which if exposed to moistair is transfbrmed into a yellow derivative of the dyestufi'.

The final product after addition of the product from pyridine and methylchlor-sulphonate to the suspension of the red substance and working upis closely related in properties to the methyl pyridinium salt of thedisulphuric acid ester of leuco indigo which appears to have the formulaindicated in Fig. 1.

Example 2 This deals with dimethoxy-dibenzanthrone, methyl chloride,zinc and pyridine followed by treatment with pyridine sulphur trioxide.

4 parts of dimethoxy-dibenzanthrone and 3 parts of zinc are suspended in28.5 parts of pyridine containing 4.3 arts of methyl chloride in anatmosphere of nitrogen. The temperature of the mixture is slowly raisedto 75 at about which temperature the meltbecomes a deep blue andthickens considerably. Themelt is stirred for 5-10 minutes and thencooled to 20 at which temperature 8 parts of pyridine sulphur trioxideare added. The melt immediately becomes a bright crimson. Thetemperature is then raised to 55 during about 20 minutes and kept at 55for half an hour, after which time it is cooled, mixed with about 250parts of a 5% sodium carbonate solution and steam distilled. When aparently all the pyridine has been remove the liquid is filtered hot andthe stable soluble derivative precipitated as a red solid from thefiltrates b addition of common salt.

The re solid appears to consist mainly of the sodium salt of adisulphuric acid ester of dihydro-dimethoxy-dibenzanthrone and to have aformula-as indicated in Figure 2, associated with water ofcrystallization.

Example 3 This deals with thin-indigo, ethyl bromide, zinc and pyridinefollowed by treatment with pyridine sulphur trioxide.

A well stirred mixture of 50 parts of pyridine, 11 parts of thio-indigoand 8 parts of zinc dust is heated to in an atmos here of nitro en. 0.75part of ethyl bromide is then added. The temperature is maintained at 70for 20 minutes when the melt changes to blood red, then to green andthen to greenish yellow. It is cooled to 20 and 20 parts of pyridinesulphur trioxide added. The temperature is then raised to 50 durin halfan hour and kept at 50 for half an our. The final colour of the melt isa gre ish white. The melt is then mixed with a ut 400 parts of watercontaining 30 parts of sodium carbonate and steam distilled. Afterapparent removal of the pyridine, the extract is filtered and thethio-indigo derivative allowed to crystallize out. The product remainingin the mother liquor may be substantially separated, either byconcentration in vacuo and subsequent crystallization or by salting outwith common salt.

The product appears to be the sodium salt of the disulphumc acid esterof dihydrothioindigo and to have the formula indicated in Figure 3,associated with water of crystallization.

Example 4 This deals with thio-indigo, methyl chloride, zinc andpyridine followed by treatment with dimethyl aniline sulphur trioxi de.

6 parts of thio-indigo, 2 parts of zinc and 30 parts of pyridinecontaining 1.4 parts of methyl chloride are heated to 60 for 10 minutes.The green brown melt is then cooled to 20 at which temperature 12 partsof dimethyl-aniline-sulphur trioxide are added. The temperature israised to 50 and kept at 50 for half an hour. The melt is then worked uwith sodium carbonate as described in xample 3.

Emwmple 5 This deals with dimethoxy-dibenzanthrone, ethyl bromide, zincand yridine followed by treatment with pyridine sulphur trioxide.

10 parts of dimethoxy-dibenzanthrone, 5 parts of zinc and 25 parts ofpyridine are stirred together in an atmosphere of nitrogen. The melt isheated to 35 at which temperature 0.75 part of ethyl bromide is added.The tem erature is now raised to 70 and kept at 70 or 20 minutes, duringwhich eriod the melt becomes blue and thicker.

t is then cooled to 20 at which tem erature 12 parts of pyridine sulphurtrioxi e are emma added. The melt becomes immediately crimson. Thetemperature is raised to 75 during 15 minutes and kept at 70-75 for halfan hour. It is then worked up with sodium carbonate as described inExample 2.

Example 6 are heated slowly to 70 with good stirring.

6 grams of copper powder'are then slowly added so that the temperaturedoes not exceed 75. When all the copper has i been added the temperatureis maintained at 7 5 for 30 minutes. The melt is then poured into watercontaining sodium carbonate and. worked up on the lines of Example 2.

Modifications may be made in the process indicated. For example, othervat .dyestufi's may be used as the starting point, other metals employedin place of zinc, other bases besides pyridine and other reagentsbesides methyl chlor-sulphonate or others mentioned, for example ethylchlor-sulphonate, sulphuric acid chloride or oleum or sulphur trioxideor the like. As above indicated the reaction according to the presentinvention may if desired be carried out in an inert atmosphere. Theinert atmosphere is not always necessary but in those cases where theintermediate product formed with the dyestufi is unstable the inertatmosphere is often of advantage.

Quaternary ammonium halides, as referred to herein, are substances suchas may be obtained by reaction between a tertiary organic base and analkyl halide.

The invention may be combined with any of the processes of thespecifications referred to above or like processes.

Among the dyestuffs which may be employed according to this inventionspecific reference is made to Indigoid and thio-indigoid 'dyestufisincluding indigo and dichlor and dibrom' in-.

digo. Anthraquinone vat dyestufls, including dibenzathrone, indanthrone,flavanthrone and anthraquinone acridone dyestuffs.

In general among the substances which may be dyed or printed eflectivelyby the above process may be noted cotton, wool, natural and artificialsilk and other animal or vegetable fibres.

Some of the products prepared according to the present invention aresoluble in solvents other than water, for example pyridine and alcohol.

The colours may in general be developed after dyeing or printing byemployment of acid oxidizing agents and in some cases alkaline oxidizingagents, for instance on the lines of British ,speclfication No. 251,491,filed on November 1st, 1924, accepted on May 3rd, 1926, and nowavailable but not published at the priority date of the present application.

Having now described our invention, what we claim as new and desire tosecure by Letters Patent is 1. The process for the manufacture ofderivatives of vat dyestuffs which consists in reacting on a vatdyestufi' with a quaternary ammonium halide, a metal, a tertiary organicbase and pyridine sulphur trioxide.

2. The process for the manufacture of the derivatives of vat dyestufi'swhich consists in reacting on a vat dyestufi with a regent comprising aquaternary ammonium halide, a metal and a tertiary organic base andtreating the product With pyridine sulphur trioxide.

3. A process for the manufacture of derivatives of vat dyestufiscomprising treating a tertiary organic base with an alkyl halide,emplpying'the resultant product to act in tertiary organic basicsuspension with a metal, a vat dyestufi' and a product obtained by theinteraction of a tertiary base with a reagent adapted to yield thesulphuric anhydrid-ecompound of the tertiary base.

' 4.. A process for the manufacture of derivatives of vat dyestuffswhich comprises the treatment of the vet dyestufi with a quaternaryammonium halide, a tertiary organic base and a metal, the product of thereaction then being treated with a compound of a tertiary base formed bythe addition of a reagent adapted to yield the sul huric anhydridecompound of the tertiary ase.

5. A process as claimed in claim 4 in which the reaction bet-ween thevat dyestufi', quaternary ammonium halide, tertiary orgamc base metal,and sulphuric anhydride compound of the tertiary organic base is carriedout in an inert atmosphere.

6. A method as claimed in claim 4 in which the product is worked up byalkali treatfiient and substantial removal of the organic ase.

7. A process as claimed in claim 4 in which the tertiary base employedis pyridine.

8. A process as claimed in cla1m4 in which the dyestuif chosen is thioindigo.

9. A process as claimed in claim 4 in which the quaternary ammoniumhalide is a pyridinium alkyl halide.

10. A process as claimed in claim 4 in which the quaternary ammoniumhalide is ethyl pyridinium bromide.

11. A process for the production ofderivatives of thio-indigo accordingto which 50 parts of pyridine, about 11 parts of thioindigo and about 8parts of zinc dust is heated to about 7 0 C. in an inert atmosphere,about 0.7 5 part of ethyl bromide is then added, the

vfibres for which the slight a temperature is maintained at about 70 C.for about 20 minutes, the melt is then cooled to about 20 C. and about20 parts of pyridine sulphur trioxide are added, the temperature is thenraised to about 50 C. during about hour and kept at about 50 C. forabout A hour, after which the melt is mixed with about 400 parts ofwater containing about 30 parts of sodium carbonate and steam distilled,after which the extract is separated and the thio-indigo derivati ecrystallized out.

12. A thio-indigo derivative which is sub stantially identical with thatobtainable by the process of claim 11 which is a colorless crystallinebody slowly becomin pinkish on exposure to light and air, reach? solublein Water and revertin to thio-in igo by the addition of acid oxi izingagents to its aqueone solution, but having little or no aflinity fortextile fibres, with the exce tion of animal ity increases on rise oftemperature t In testimony-whereof we have signed our namesto this secification.

U H ALBERT EDWARD DRESCHER. JOHN EDMUND GUY HARRIS. BIRKETT WYLAM.

. JOHN THOMAS.

